The SFLFP123 batteries are the perfect solution for customers who prefer to use rechargeable 123A cells when powering SureFire illumination tools, including WeaponLights and hands-free lights. While they lack the capacity of SureFire 123A lithium primary cells, SFLFP123 cells are safe to use, cost-effective, and they retain approximately 80 percent of their original capacity even after hundreds of charging cycles.Features :SFLFP123 batteries are rechargeable and reusable, saving you hundreds over 123A lithium primary batteriesSFLFP123 batteries are better for the environment because they contain no hazardous heavy metalsSmart, internal circuitry automatically terminates charge cycle when cells are at full capacitySafety design features provide protection from overcharge, short-circuit, and reverse polarity